1. Field of the Invention
The present invention relates to a "yoke" apparatus for use on an oil drilling platform. More particularly, the present invention relates to a circular yoke apparatus which is adapted to be secured around the flange of a splined coupling to shift the coupling between the splined shafts of the hydro-brake and a draw works on an oil well drilling platform.
2. General Background
In the oil drilling industry, and particularly in the actual drilling process done on the oil rig itself, the primary apparatus for performing the actual rotation of the drilling bits as the oil is being drilled is called the draw works. Also, the draw works is required to support the drilling pipe commonly known as the drill stem during the drilling operation. The hydro-brake acts as a holding brake to slow down the draw works and to hold back a part of the weight of the drill string thus assisting the draw works in its braking and over all control of the drilling operation. This braking apparatus is connected to the draw works through a mating of the hydro-brake shaft and the draw works shaft. When the hydro-brake is unneeded in the drilling operation, one could release the connectable mating of the shafts, and leave the hydro-brake idle while the draw works continued in the drilling operation.
An essential part of the mating of the hydro-brake shaft and the draw work shaft via the splined coupling is the fact that the coupling is housed in a yoke or collar unit. At the present time the type of unit which is utilized is simply a metal collar having inner directed edges which would simply fit around the splined coupling, with the yoke being mounted on a pair of leg or the like supports rigidly attached to the floor. The yoke simply serves as a housing unit for the splined coupling which, when the hydro-brake and the control work shaft are coupled together, the rotation of the shaft imparts rotation of the splined coupling within the yoke housing. In the present state of the art, with the yoke being simply a bare metal collar, the rotation of the splined coupling, which is at times at great speeds, tends to wear away the yoke within 2 to 3 months time on an oil rig, thus requiring that the yoke be changed. At the present time, when the yoke must be changed, the draw works and the hydro-brake must be stopped, the yoke removed and a new yoke put in place. This time spent in changing the yoke, is of course, down time for the rig, which means loss of money and efficiency in the oil drilling process.
In the present state of the art, there are apparently no patented devices which would be utilized in serving as a collar or a yoke splined coupling between a hydro-brake and draw works having the features of our present apparatus.
The following patents were found as being the closest art available:
U.S. Pat. No. 696,973 issued to G. L. Holmes, entitled "Clutch Operating Device" would teach the use of the means and devices for operating clutch mechanisms or form operating mechanisms wherein the part is to be moved to the limits of its excursion and to opposite directions, and is in each case expected to remain securely in the new position. The patent simply discloses a functional stand for lateral movement of a ring device, having somewhat of the structural features of the apparatus in the present invention.
U.S. Pat. No. 643,126 issued to G. G. Guy et al, entitled "Water Crane" discloses the use of a collar and roller or ball bearings in facilitating rotation of the joint.
U.S. Pat. No. 1,796,473 issued to Nixon, entitled "Bearings" and U.S. Pat. No. 728,499 issued to Reuder entitled "Motor Vehicle" disclose the broad concept of providing bearings in a machine element to relieve thrust friction with another machine element held therebetween.
None of the patents as cited or other patents as found in the art, would disclose the use of the yoke apparatus combination with the thrust bearings and means for lubricating the bearings for use with engaging a splined coupling between a drill works and a hydro-brake on a drilling well.